Child DevelopmentChild DevelopmentChapter 4: Prenatal Development

JournalJournalWrite down 5 phrases that

explain what you know about pregnancy.

State StandardsState Standards3.1 Analyze hereditary and

environmental factors affecting prenatal development beginning with conception

3.2 Analyze maternal and paternal health and environmental factors affecting conception and prenatal development

VideoVideoBrain Pop-Reproductive System

ConceptionConception

Vocabulary•Ovum•Uterus•Fallopian Tube•Sperm•Conception

Family PlanningFamily PlanningThe only 100% method of

contraception is abstinence An ovum usually lives 12-24

hours A sperm usually lives 48-72 hours There are approximately 3-4

days in which intercourse could lead to conception

Contraceptive MethodsContraceptive MethodsGroups 1-2 Each group will have 1 method. Your responsibilities:

◦Find a picture of an example of that method

◦Turn picture into the assignment turn in folder

◦Give a 30 second spill about that method and show picture

Grade: Assignment worth 20 points◦5 points for picture◦10 points for spill◦5 points for professionalism

Brainpop VideoBrainpop Video“Genetics”

Genetic PackageGenetic Package

Each person inherits characteristics from parents

Chromosomes: tiny threadlike particles in the nucleus of every cell◦ Human babies receive 46 at conception- 23 pairs◦ Each chromosomes has thousands of genes: the units

that determine inherited characteristics◦ For every inherited characteristic a person receives two

copies of a gene- mother and father◦ Dominant Gene: stronger◦ Recessive Gene: weaker◦ Genome: The complete blueprint for the creation of a

person

Making a Unique PersonMaking a Unique PersonFamily often times look alike

because of the gene combinations

Sex of a child is also determined at conception

Two types of sex chromosome: X and Y

Egg cells contain XSperm cells contain wither X or Y

Brainpop VideoBrainpop Video“Heredity”Punnett Square Activity

JournalJournalWhat is infertility?Name two other options an

infertile mother would have?What is the difference between

identical and fraternal twins?

Multiple BirthsMultiple Births

Identical Twins: Fertilized egg divides into two separate babies

Fraternal Twins: two eggs are released at the same time and both are fertilized

2.5% of births are multiple births◦More than 2 babies is even more rare◦Most of the time multiple births (more than

2) results from treatment of infertility: the inability to become pregnant

InfertilityInfertilityNot all people are able to

become pregnant1st step: Doctor evaluates both

parent’s help to determine causeFertility drugs may be prescribed

if the cause is eggs are not released every month◦Several drawbacks: serious side

effects, multiple births, etc

Options for InfertilityOptions for InfertilityAfter treatment for infertility some

people are still not able to conceiveSome options:

◦ Adoption◦ Artificial Insemination: sperm injected into

woman’s uterus◦ In vitro Fertilization: Egg is fertilized outside

body and then placed in the woman’s uterus◦ Ovum Transfer: egg from female donor then

fertilized◦ Surrogate Mother

Three Stages of Three Stages of PregnancyPregnancyPrenatal Development: the

baby’s development during pregnancy

Germinal StageEmbryonic StageFetal Stage

Germinal StageGerminal StageZygote: The fertilized eggLasts only about 2 weeksCell Division

◦Cell begins to grow while it is still in the fallopian tube

◦After about 4 days the zygote reaches the uterus

Implantation After about 2 weeks of growth the

zygote is about the size of a pin head

Embryonic StageEmbryonic Stage Embryo: developing baby from weeks 3-8 Organs and Body Systems:

◦ All the major system develop in this stage◦ Brain begins to take control◦ Brain is sensitive to damage from drugs and alcohol

Amniotic Sac Amniotic Fluid Placenta: Tissue that connects the developing baby to

the uterus Umbilical Cord: long tube that connects the baby to

the placenta Placenta and Umbilical cord are responsible for taking

waste away from and bringing nutrients to embryo

Fetal Stage Fetal Stage Fetus: developing baby during the

fetal stageVocal chords developDigestive system and kidneys begin

to functionMovements are possible by the end

of the 3rd monthBy 7th month fetus is capable of

living outside uterus but will require medical intervention

Fetal Stage, ContinuedFetal Stage, ContinuedFetus can

◦Suck thumb◦Cough◦Sneeze◦Yawn◦Kick◦Hiccup◦Cry

Preparing for BirthPreparing for Birth

Baby’s weight begins to shift down in 9th month- “lightening”

Fetus is turned upside down in mother’s pelvis

Less activeMuscles of the uterus and abdomen

can be stretched up to 60 times their original size!◦Return to original size in about 6 weeks

after pregnancy.

JigsawJigsawDescribe what happens during

fetal development for given month in pregnancy◦Size of fetus◦Organs developed◦Important Developments

Brainpop VideoBrainpop Video“Fetal Development”

Section 5-3Section 5-3Problems in Prenatal Development

For DiscussionFor DiscussionExcerpt from Helen Keller’s The

Story of My Life

ObjectivesObjectivesContrast miscarriage and

stillbirthIdentify some major birth defectsExplain the four causes of birth

defectsDescribe how birth defects can

be diagnosed and prevented

Key TermsKey TermsAmniocentesisBirth DefectChronic Villi SamplingMiscarriageStillbirthUltrasound

Losing a BabyLosing a BabySometimes babies do not

develop normallyIn some cases the developing

baby will dieBefore 20 weeks- miscarriageAfter 20 weeks- still birthLoss of an unborn child is

devastating to parentsAs many as 20 percent of al

pregnancies end in miscarriage

Types of Birth DefectsTypes of Birth Defects

Birth defect- serious problems that threatens a child’s health or ability to live

About 3 out of 100 children are born with a birth defect

Birth defects affect:◦ Shape or size of the body or of certain parts of the

body◦ A part or system of the body does not work properly

Not all birth defects are apparent at birth

Causes of Birth DefectsCauses of Birth DefectsScientists still don’t understand

the cause of all birth defectsThere are 4 main causes

Environmental CausesEnvironmental CausesDuring the first few weeks of

conception all the baby’s major systems develop

Things that affect the development of the baby include:◦ Nutritional balance of the mother’s diet◦ Diseases or infections the mother has ◦ Harmful substances the mother takes in◦ Some medicines◦ Exposure to outside hazards such as radiation

Hereditary CausesHereditary CausesThousands of genes make up a genetic

blueprint- each person has about 5-6 imperfect recessive genes

A single copy of this defective gene- no effect

2 copies of this gene=birth defect or a dominant defective gene=birth defect

Some inherited conditions affect only one sex◦ Ex- Hemophilia (prevents blood from clotting)

and color blindness

Errors in ChromosomesErrors in ChromosomesSome birth defects are linked to a

problem with the baby’s chromosomes◦Ex- too many or too few chromosomes

The child does not inherit this condition

Most common is down syndrome◦1 child in every 800 births has down

syndrome◦Risk is higher in mothers over 35◦Child has an extra chromosome 21

Interaction of Heredity and Interaction of Heredity and EnvironmentEnvironmentSometimes birth defects result

from heredity and environment combined◦Ex- A baby may inherit the tendency

for a heart defect but only appears if some factor- such as a drug or virus- affects the baby during development

Researchers think this is probably the cause of cleft lip and spina bifida

Prevention and Diagnosis of Prevention and Diagnosis of Birth DefectsBirth DefectsChildren with birth defects have

difficulty leading normal livesThe rest of the family is affected

tooResponsible couples do

everything possible to minimize the possibility of birth defects

Genetic CounselingGenetic CounselingSome people seek genetic counseling

◦ May or may not already have a child with a birth defect

Does not tell people what to do, only explains risks and options

Family doctors can perform this service, but is best provided by a specialist

The genetic counselor first gathers family histories from the couple

Then they are given thorough medical examinations and sometimes tests

Prenatal TestingPrenatal TestingMore than 100 birth defects can now be

found before a baby is bornThere is not a test to tell if a child will

be normalThese tests can alert the physician of

problems; many times they can be taken care of before birth or immediately following birth

Sometimes blood testing can reveal birth defects

Types of Prenatal TestsTypes of Prenatal Tests

Ultrasound- checks for specific health problems◦ Can show if the fetus is developing on schedule◦ Can confirm due date

Amniocentesis- Process of withdrawing a sample of amniotic fluid and then testing it for indications of birth defects◦ About 1 out of 200 amniocentesis tests result in

miscarriage Chronic Villi Sampling- Tests a small amount of the

tissue surrounding the fetus◦ Guided by a ultrasound image the doctor inserts a small

tube throught the woman’s vagina into the uterus; the samples are then obtained by snipping or suction

◦ Risk of miscarriage or birth defect is mush higher than amniocentesis

Ask the ExpertsAsk the ExpertsP. 163

Section 5-4 Section 5-4 Avoiding Dangers to the Baby

Key TermsKey TermsFetal Alcohol effectsFetal Alcohol Syndrome

ObjectivesObjectivesIdentify the hazards that alcohol

and other drugs pose to prenatal development

Discuss other environmental hazards that pregnant women should avoid

AlcoholAlcohol

Alcohol is a drugFetal Alcohol Syndrome- a pregnant

woman who drinks is at risk for her child developing FAS◦Includes physical and mental problems◦1 in 5 babies with FAS die soon after birth◦Almost all are mentally retarded◦Other problems: slow growth, poor

coordination, heart defects, and facial disfigurement

◦Also, learning disabilities and hyperactivity

Alcohol, continuedAlcohol, continued

Fetal Alcohol Effects- less severe than FAS, but still suffers from some of the same problems

Severity depends on amount consumed by mother, stage of pregnancy, and presence of other drugs in the mother’s system

Can be prevented by not drinking!It is not know how much alcohol will

cause the syndrome

Other DrugsOther DrugsPrescription and over the counter

drugs◦No such thing as a completely safe drug◦First 3 months are most critical◦Last 6 months- slowed growth,

infections, and bleeding at birth◦Meds should not be taken unless

approved by the doctorCaffeine- also a drug, can cause

birth defects as well, not sure about amounts

Other Drugs, continuedOther Drugs, continued

Tobacco- the more a mother smokes the smaller the baby will be ◦ Heavy smoking can cause premature birth◦ Linked to respiratory infections, allergies, and asthma

Illegal Drugs- a mother who is addicted to an illegal drug normally passes the addiction to the baby◦ After birth the baby must go through withdrawal,

some babies die◦ Long-term effects may be serious, many of these

children have problems following directions and learning disabilities

X RaysX RaysRadiation can cause birth defects

as wellPregnant women should warn

medical personnel Always request abdominal

shields during x rays

RubellaRubellaWhen a pregnant woman

contracts rubella babies can suffer with deafness, blindness, heart disease, or mental retardation

Vaccines are available but can be dangerous for women who are pregnant or become pregnant shortly after the shot

Sexually Transmitted Sexually Transmitted DiseasesDiseasesInclude: Syphilis, Gonorrhea,

Hepatitis B, Genital Herpes, AIDS, Group B Streptococcus, Chlamydia

Can be passed from mother to child

Can result in death or other birth defects

You can have a STD without knowing it!

AIDS- the virus that causes AIDS can be passed from mother to child